Type-bar-actuating mechanism



Oct. 7, 1930. GARBELL 1,777,465

TYPE BAR ACTUATING MECHANISM Filed Dec. 1927 Z 12 91 5; 10 414 06?flfiaw $71M %M Patented Oct. 7, 1930 UNITED STATES PATENT OFFICE MAXGARBELL, OF CHICAGO, ILLINOIS, ASSIGNOR TO VICTOR ADDING MACHINE COM-PANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOISTYPE-BAR-LACTUATING MECHANISM Application filed December 5, 1927. SerialNo. 237,596.

The present invention relates to an improved type-bar actuatingmechanism for typewriters, and comprises novel means for taking up theshock upon the key-levers concomitant with the sudden arrest of themechanism when the type-bars makecontact with the platen when in theprinting position.

This invention is an improvement upon that disclosed and claimed in myco-pending application, Serial No. 720,255, filed June 16, 1924, forTypewriting machines, and assigned to the assignee of the presentapplication. I

One of the objects of my invention is to provide resilient meansallowing the keylevers to make a slight downward movement when thetype-bar strikes the platen, and to accomplish this by a novelarrangement of key-levers, intermediate links, type-bars andsprings, aswill be clearly set forth hereinbelow.

A further object of my invention is to pro- .vide a type-bar actuatingmechanism which makes the touch of the typewriter to which it is appliedvery smooth and velvety, and also contributes partly to silent andeflicient operation. These advantages are particularly manifest when mysaid type-bar actuating mechanism is applied to portable typewriters.

In its essential features my new mechanism comprises a pivoted type-barprovided with a gear at its pivoted end, a pivoted intermediate leverprovided with a gear at its free end intermeshing with the gear on thetypebar, a pivoted key-lever having a link pivoted to the same and whichlink engages a slot in the aforesaid intermediate lever, the connectionpreferably, but not necessarily, being accomplished by means of a rolleron a pin at the end of said link. There is further provided a tension, acompression or a leaf spring biasing said,link in one direction, and astop on the key-lever limiting the pivotal motion of the said link inasimilar direction, so as to compel the sliding connection in the slotof the intermediate lever to move in a certain direction, but whichdirection will be reversed the moment the type-bar strikes the platen,so that the key-lever will make a further slight movement downwardly,giving what might be termed a cushioning or shock-absorbing effect.

The advantages of this arrangement are manifold, as the type-bar actionwill be remarkably smooth and free from jerkiness, and the touch of themachine will approach or excel that produced by having rubber orspring-cushioned key-covers on the end of the key-levers.

My present invention is illustrated upon the drawings which accompanyand form a part of the present application. In these drawings:

Figure 1 is a side elevational view of my improved type-bar shown in theposition at rest, that is to say, when the type-bars are resting againsttheir support and the key-levers are in their normal position ready foruse.

Fig. 2 is a similar view of the same parts in the position at the momentwhen the typebars with their attached type-characters make contactagainst the paper or platen of the typewriter.

Fig. 3 is a similar view showing the same parts in the position theyassume when the hey-lever is further pushed downwardly but while themovement of the intermediate lever and type-bar is arrested by virtue ofthe contact of the said type-bar with the platen of the typewriter.

In all three figures similar characters refer to similar parts.

My improved type-bar actuating-mechanism comprises a suitably shapedtype-bar 1 having a pivot 2 and provided with a gear 3 at the pivotedend. Suitable type-characters 4 are located at the free end of thetype-bar 1, and, when the type-bar 1 is in the printing position, makecontact with the platen 5. A suitable gear 6 on a pivoted intermediatelever '7, which is supported by the pivot 8, inte'rmesh with the gear 3of the said typebar 1. A. slot 9 in the said intermediate lever 7 is inengagement with a pin and roller 10 located at the end of anintermediate link 11, which is pivoted at its other end 12 to akeyactuating mechanism lever 13 having a pivot 14 at one extremity, anda key at the other end.

The intermediate link 11, which is free to rotate upon its pivot 12 isprevented from g movement in one direction by a stop 15, and

spring.

In order to insure the return of the mechanism to itsfat rest positionafter a printing stroke, a spring 17 attached to a projection 18 on thekey-lever 13 is provided. Furthermore, provision may also be made forpreventing the actuation of an universal bar that actuates the carriageescapement by forming a recess 7 in the intermediate lever into whichthe said universal bar 7 will fit when the lever 7 is at its lowestdownward stroke.

It should be noted that on all these figures there is a reference lineC-C passing in a vertical direction through the intermediate link 11 andits pivot 12, as the action of my improved mechanism can bestbeunderstood by the following description and the said reference line.r.

The action of the mechanism made in accordance with my present inventionis substantially as follows, reference being had to Figs. 1, 2 and 3,which show three different positions assumed by the said mechanism.

When the mechanism is at rest, as shown in Fig. 1, it will benoticedthat the link 11, the roller 10 and the pivot 12 all liesubstantially on a vertical line CC' passing through the said points.

When the key-lever 13 is depressed, as by striking the key, theintermediate link 11 will exert a downward pull on the intermediatelever 7, thus causing the free end of said lever 7, bearing the gear 6,to move downwardly and, by reason of its engagement with the gear 3 onthe type-bar 1, to cause the latter to swing about its pivot 2 and to aproach the platen 5, eventually, at the end of the stroke, contactingwith the same by its type-characters 4.

Were it not for the spring 16 biasing the said intermediate link 11 andholding it against its stop 15 on the key-lever 13,- the tendency of therolling connection made by the roller 10 in the slot 9 on theintermediate lever 7 would be to move said roller downwardly (to theright in the drawings) and the link 11 would attempt to align itself insuch a way as to make a right angle with the sides of the slot 9. Thisis caused by the fact that link 11 is pivoted to key-lever 13 at 12, sothat theroller 10 on the end of the lever 7 is, however, pivoted at 8,the said slot Q will swing on an are having 8 as its center.

By reason of the spring 16, the intermediate link 11 will be forced tofollow a different movement, namely its end 10 will be compelled to moveon an arc of a circle the center of which is at the key-lever pivot 14,just as would be the case if the intermediate link had been madeintegral with the key-lever 13. This are is shown in dotted lines on allthree figures and is designated as A14:. The arcs having their centersat pi'vots 8 and 12, respectively, are likewise shown in dotted linesand bear the indicia A 8 and A12.

As the weight of the type-bar 1 is in actual practice counterbalanced bythe weight of the intermediate lever 7 and the weight of the key-lever13, there will be but a very slight tendency for the elongation of thespring 16 as long as there is nothing to interfere witn the freemovement of the various parts of the mechanism. As a result of this, themechanism will assume the position as shown in Fig. 2, which shows themechanism at the instant when the type 4 make their incipient contactwith the platen 5. It should be noted that now the roller 10 on the endof the intermediate link 11 has moved toward the left along the arc A14,and now no longer points vertically but lies to the left of the verticalcenter-line CC. Thus far the spring 16 has' served merely to keep thelink 11 against the stop 15.

Now, as shown in Fig. 3, when the movement of the type-bar 1 isinterrupted by its coming into contact with the platen 5, it

will, by virtue of the engagement of the gears 3 and 6, likewise preventthe further movement of the intermediate lever 7 about its pivot 8. Asthe pressure on the key at the end of key-lever 13 is howevermaintained, the key-lever 13 will continue to move about its pivot 14.The intermediate link 11, were it integral with key-lever 13 wouldprevent this motion and as a result the key at the end of the key-leverwould impart a distinct shock to the finger of the operator by reason ofthe sudden stopping of the mechanism.

- In the construction accordin to my invention, however, and especiallyecause of'the spring 16 and the pivot 12, the key-lever is permitted tomove downwardly a short distance. while the roller 10 slides down alongthe slot 9 in the intermediate lever 7, so that now the said roller willmove along the arc A-12 having its center at the pivot 12 of the saidintermediate link 11. It should be particularly noticed that this exertsa slight upward push on the intermediate lever 7, as the movement of theroller 10 is not in a straight line, but on an arc, and hence the willbe slightly retracted, which is just what is desired in a typewriteraction; in other words the impression will not be dead but snappy.

On releasing the key, the spring 16 will tend to return the link 11 toits original position, and the spring 17 on the key-lever will returnthe latter to its original position so that the entire mechanism willresume its position as shown in Fig; 1.

Attention is directed to the fact that the intermediate link 11, at thefinal position of the stroke, will lie to 'the right of the centerlineCC, as shownin Fig. 3. The position of the key-lever 13 and link 11 atthe end of the stroke is also shown in dotted outlines superimposed uponFig. 2. It will thus be seen that the spring 16 will only be underincreased tension at the extreme end of the stroke, and as I contemplatemaking this spring of such strength that it will not move materiallyuntil the type-bar strikes the platen, it will act as an efiicient shockabsorber for the keys.

Obvious modifications may be made without departing from the scope of mypresent invention. What I claim is:

1. In a type-bar action, a key-lever, a typebar, an intermediate lever,and a connection between said intermediate lever and said key-lever,comprising a link pivotally mounted on said key-lever and moving in aslot in said intermediate lever, said link being spring restrained inone direction to permit the keylever to continue its movement after thecompletion of the printing stroke of said typebar and at the same timeto give said typebar an initial kick-back.

2. In a type-bar mechanism for typewriters the combination of a pivotedkey-lever, a

link pivoted to the same, a pivoted intermediate lever having a slot,connection between said slot and said link comprising a pin thereon, apivoted type-bar, and gears on said type-bar and intermediate leverengaging each other.

3. In a type-bar mechanism for typewriters the combination of a pivotedkey lever, a link pivoted thereto, a stop on said key-lever limiting themovement of said link in one direction, a spring biasing said linkin thedirection of said stop, a pivoted intermediate lever having a slot,connection between said slot and said link comprising a pin and rollerthereon, a pivoted type-bar and gears on said type-bar and intermediatelever engaging each other.

4. In a type-bar mechanism for typewriters comprising a key-lever and aslotted intermediate lever, the combination of a connecting link pivoted.on said key-lever and having a portion engaging the slot of saidintermediate lever, a stop onsaid key-lever limiting the pivotalmovement of said link in one direction and a spring biasing said linkagainst said stop.

5. In a type-bar mechanism for typewriters comprising a slotted pivotedintermediate lever connected with a link by means of a pin, thecombination of resilient means biasing said link in a direction towardthe pivot of the intermediate lever.

6. In a type-bar action mechanism for typewriters, the combination of akey-lever, a link pivoted thereto, an intermediate lever having a slotengaging a roller on the free end of said link, a spring biasing thelink in a direction toward the pivot of said intermediate lever, and astop limiting the movement of said link.

7. In a type-bar action for typewriting machines, the combination of akey-lever pivoted at one end, a link pivoted to said keylever, a slottedintermediate lever pivoted at one end and having a gear at its free end,a pin on said link in sliding engagement with said intermediate lever,and a pivoted typebar having a gear at its pivoted end, said gears beingin engagement with each other.

8. In a type-bar action for typewriting niachines, the combination of akey-lever pivoted at one end, a link pivoted at one end'thereof to saidkey-lever, a stop to limit the pivotal motion of said link in onedirection, an intermediate lever pivoted at one end and having a gear atits free end and a slot near the pivoted end, a pin on said link insliding en gagement with said intermediate lever, and a pivoted type-barhaving a gear at its pivoted end in engagement with the teeth on saidintermediate lever.

9. In a type-bar action for typewriting machines, the combination of akey-lever pivoted at one end, a link pivoted at one end thereof to saidkey-lever, a stop to limit the pivotal motion of said link in onedirection, an inter- .mediate lever pivoted at one end and having a gearat its free end and a slot near the pivoted end, a pin on said link insliding engagement with said intermediate lever, and a spring tending toforce said link toward the said stop.

10. In a type-bar mechanism for typewriters comprising a key-lever, aslotted and pivoted intermediate lever, and a pivoted link on saidkey-lever having a pin in slidable en' gagement with said slot, thecombination of a stop on said key-lever and a spring connecting saidkey-lever and said link, said stop limiting the pivotal movement of saidlink in one direction and the spring biasing said link against saidstop.

11. In a type-baremechanism for typewriting machines having a pull-barpivoted to a key-lever and having said pull-bar in slidable engagementwith a slot in an intermediate lever by means of a pin, the combinationof means for limiting and controlling the movement of said pull-armcomprising a resilient connection between the said pull-arm and saidkey-lever and a stop on said key-lever.

12. In a type-bar mechanism for typewriters, a key-lever and resilientmeans for taking up the shock when the key-lever reaches the extremelower end of its stroke comprising a link pivoted on saidkey-lever, astop on said key-lever in fixed relation to the pivot point of saidlink, and a spring biasing said link toward said stop.

In witness whereof, I have hereunto subscribed my name.

MAX GARBELL.

Certificate of Correction Patent No. 1,77 7,465.

MAX GAR BELL.

Granted October 7, 1930, to

It is hereby certified that error appears in the above numbered patentrequiring correction as follows: After the heading to the printedspecification beginning with line 1, page 1, strike out all printedmatter to the end of the specification including the claims, and insertinstead the following:

My present invention concerns a mechanism which presents peculiaradvantages from the viewpoints of ease of assembly, cheapness ofmanufacture, and a minimum of parts. 7

This invention is an improvement upon that disclosed and claimed in myco-pending application, Serial No. 720,255, filed June 16, 1924, forTypewriting machines, and assigned to the assignee of the presentapplication.

One of the objects of my invention is to provide a type-bar mechanismcomprising a pivoted key-lever, a pivoted intermediate lever, and apivoted type-bar, in which the key-lever is connected to theintermediate lever in such a way that the point connecting the two willmove substantially in a straight line, so that. there will be a mini--mum of friction and at thesame time a certainty of action not hithertoattained by mechanisms similar to the one that forms the subject matterof my present invention.

Another object of my invention is to reduce the number of parts requiredin making a type-bar actuating mechanism, by providing a lateral armintegral with a keylever and connected with an intermediate lever bymeans of a pin and slot, the pivotal points of the key-lever.intermediate lever, and type-bar being so located as to present certainadvantages which will be more fully set forth hereinbelow.

In the drawings which accompanying the present specification, Figure 1is a diagram matic side elevational view of the type-bar actuatingmechanism, made in accordance with my present invention, shown at itsnormal position of rest;

Fig.2 representsthe same mechanism in its position at the extreme end ofthe printing stroke, the said Figs. 1 and 2 also having certaingeometrical lines upon thersame showing the alignment of pivotal pointsand the arcs upon which various parts of the mechanism swing when theyare moved.

3 is an enlarged view of the slot and upon a suitable piece of paper orother material placed upon the platen 5. There is also an intermediatelever 7 having a gear segment or teeth 6 and pivoted about the point 8.The said intermediate lever also has a slot 9 capable of engaging a pinor roller 10 upon the vertical arm 11 of a key-lever 12, the latterhaving a pivot 13 at one end.

The pivotal points 2 and 8 and the pointof connection of the arm 11 at.the pin or roller 10 form a straight line A-A as shown in Fig. 1 whenthe mechanism is in its normal at rest position. The pivotal points Sand13 at the point of attachment of the pin or roller 10 will also formastraight line when the mechanism is in the furthest advanced printingposition, as shown in Fig. '2 by the line B-B.

The teeth 3 on the type-bar andthe teeth 6 0n the intermediate lever arein such intermeshing relationship that the downward" movement of thesaid intermediate lever 7 will cause the type-bar 1 to swing about itspivot 2 and strike the platen 5. It will be noted that the intermediatelever 7 swings about the pivot 8 and the dotted circle OC shows the lineof motionjof the point 10 located centrally of the slot 9 in theintermediate lever 7. The dotted circle DD' shows the line of motion ofthe pivotal connection 10 upon the arm 11 of the key-lever 12, thecenter of this circle D-D' being at the pivot 13. i

As the resultoi the location of the pivots 8, 2, '13, and 10 it will benoticed that the direction traversed by the connecting point 10 Wherethe said arm 11. eng g the slot 9 of the key-lever 7 will be virtually astraight line, so that despite the fact that the pin entering the slot 9is free to move in said slot,

the actual movement at this .point will be negligible, and as a resultof this construction, there will be a minimum of friction at the sidesof the slot 9 and the pin 10 so thatalso be placed in a hole in theintermediate dent from the drawings and the description link if the easeof assembly incident to the slot 9 is foregone, since that point 10 doesnot move any appreciable amount along said slot, as herein afterexplained.

Provision is also made for actuation of an escapement universal bar 16by depression ofthe intermediate lever 7 and there also may be providedan additionaluniversal-bar for actuating the ribbon mechanism of thetypewriter. In order to provide for so-called dead keys, the saidintermediate lever 7 may have a recess 17 formed in the same, of suchsize and shape that the universal bar 16 may enter therein and fail tobe actuated.

ig. 3lis a fragmentary view of the intermediate lever 7. It will benoted that the enlargement 14 is of suflicient size to admit the head 10of the pin 10 which is riveted or integral with the vertical arm 11 onthe key-lever 12. Fig. 4 is a detail showing how the head of the pinprevents its withdrawal from the slot. T

In Fig. 2, it will be seen that when the typebar 1 has swung'intokv-itsextreme advanced position andhas made contact with the platen 5, thepivotal points 8 and 13 will form' a straight line with the pin 10, theline of motion of the said pin being indicated by the short heavy dottedline EE in both figures.

The action of the mechanism will be eviforming a parthereof, as thedepression of the key-lever 12 will exert a downward pull 'upon the armintegral therewith causing the intermediate lever 7 to swing about itspivot 8 by virtue of the connection made therewith by the pin 10 causingsaid in to describe anarc along the circle C while at the {same time,the pointlQ'will tend also to describe part of an are along the circleD-D by reason of. the pivotal point 13 on the keylever 12. Asthis'motion, however, is in actual practice, and-in oneexemplificationof my present invention, only about f; of an inch, it will be seen thatthere is substantially no tendency for the pin-1O to slide within theslot 9 and, therefore, sliding friction usually e cou tered in yp -a ton m h nisms simithough the arc of a second gear wheel intermeshing withthe first-mentioned gear wheel, so that the entire action would takeplace during the time one tooth was in engagement with one interdentalspace in the larger wheel.

The mechanism may be retracted to its normal position by means of aspring 15 attached to the key-lever, but it is within the scope of myinvention to employ springs upon any other part of the mechanism, providthat they perform the function of returning the same to its initialosition.

Obviously, modifications within the skill of the mechanic may be made inthe shape and in the constructional details of my herein describedtype-bar actuating mechanism, the essential feature being the alignmentof the pivotal points in such a manner as to avoid substantially allsliding friction, so that all parts will move right on the dead centersof their pivots and will therefore provide a very steady and positivetype-bar action.

Having disclosed my invention, what I desire to claim is:

1. In a ty e-bar mechanism, a pivoted 7 type-bar, a plvoted key-lever,and a pivoted in a substantially straight line when the parts are innormal position and the pivots of said intermediate lever and saidkey-lever and said connection point lying straight line when saidtype-bar is at printing position, the pivots of said key-lever, type-barand intermediate lever never being in one line, and each being locatedat one end of the respective levers and bar.

2. In a type-bar mechanism, a type-bar 'pivoted at its end, a key-leverpivoted at its end, and an intermediate lever pivoted at its end andoperatively connected atan intermediate point thereof to said key-lever,said connection point lying in a substantially straight line connectingsaid intermediate lever pivot and said type-bar pivot when the parts arein normal position, and, movable into, but not beyond, a substantiallystraight .line connecting said intermediate lever pivot and saidkey-lever pivot when the parts are moved to printing position.

'3. In a type-bar mechanism, a pivoted key-' in another lever having avertically extending arm, a

pivoted slotted intermediate lever engaged by said arm, an internal gearsegment on the free end of said intermediate lever, a pivoted typeabarhaving a gear at its pivoted end engaging said gear segment, the pointof engagement of said arm and intermediate lever being locatedsubstantially'on a straight line drawn between the pivots of theintermediate lever and the pivot of the type-bar when themechanism is inits normal position.

4. In a type-bar mechanism, a pivoted keylever having a verticallyextending arm, a pivoted slotted intermediate lever engaged by said arm,an internal gear segment on the free end of said intermediate lever, apivoted type-bar having a gear at its pivoted end and engaging saidgeansegment, the point of engagement of said arm and intermediate leverbeing located substantially on a straight line drawn between the pivotsof the intermediate lever and the pivot of the key-lever when themechanism is in the printing position.

5. In a type-bar actuating mechanism for typewriters, the combination ofa pivoted key-lever, an arm integral therewith and disposedsubstantially vertically, a pivoted intermediate lever, a slidingconnection between said arm and said intermediate lever,

a pivoted type-bar, gears connecting said in-' termediate lever andtype-bar, the point of interconnection between said arm and intermediatelever being positioned so that it will move substantially on a straightline when the mechanism is operated.

In witness whereof, I have hereunto subscribed my name. v

' MAX GARBELL.

and that the said Letters Patent should be read with this correctiontherein that the same may conform to the record of the case in thePatent Oflice.

Signed and sealed this 13th day of January, A. D. 1931.

[SEAL] M. J. MOORE,

Acting Oomnn'ssz'omr of Patents.

